


Castiel

by TFWBT



Series: Advanced Thanatology Sam Comfort [1]
Category: Supernatural
Genre: Anal Sex, Angst, Canon Compliant, Episode: s13e05 Advanced Thanatology, Episode: s13e06 Tombstone, Established Relationship, Hurt Sam Winchester, Hurt/Comfort, M/M, Past Rape/Non-con, Post-Episode: s13e05 Advanced Thanatology, Post-Episode: s13e06 Tombstone, Sastiel - Freeform, Season/Series 13
Language: English
Status: Completed
Published: 2017-12-14
Updated: 2017-12-14
Packaged: 2019-02-14 14:57:48
Rating: Explicit
Warnings: Rape/Non-Con
Chapters: 1
Words: 3,528
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13010229
Author URL: https://archiveofourown.org/users/TFWBT/pseuds/TFWBT
Summary: Sam is spun out after the events of Advanced Thanatology. Castiel provides some much-needed relief.





	Castiel

**Author's Note:**

> This is part of a series where Castiel, Dean, and Jack all comfort Sam after the events of Advanced Thanatology. Each story in the series features a different pairing. They can be read as part of the same or separate universes depending on personal preferences. The Castiel/Sam story takes place after Castiel's return in Tombstone. 
> 
> References to past Lucifer/Sam non-con in the cage.

Castiel’s not sure if Sam even wants anything to do with him, but he waits until evening, when Dean’s in bed and won't notice. They'll tell him, eventually. It's not as if they want to keep secrets from him, it's just that neither of them knows how to explain it. What ‘it’ even is. Or was. Castiel's not naive enough to imagine that his choice to leave with the Colt, or with Jack, have endeared Sam's already tumultuous feelings towards him. And those are only the most recent of Castiel’s mistakes with Sam. 

Castiel knocks. 

Sam opens the door and looks at him, an unreadable expression on his face. 

“Can I come in?” Castiel stands in the doorway as he waits for Sam to decide - whatever he chooses, Castiel will honor it. 

Sam steps to the side and motions Castiel in with a jerk of his head. 

Castiel steps into the room, grateful and ashamed that Sam can be so forgiving after everything he's done to him. He takes the chair instead of the bed. 

Sam notices, but says nothing. As he sits on the bed, he stretches out his legs on top of the covers, which are still tucked snugly in their corners. He's already in his pajamas and Castiel can't help but notice how the fabric clings to his chest and back. Castiel's cock twitches in eager excitement, but he ignores it. So much has changed since the last time they were in this room together. 

Looking at Castiel evenly, Sam says, “I suppose you want an update on everything that happened while you were…gone.” 

That isn't why he came here, but Castiel nods and Sam explains. He tells his history as if he's reciting the plot of one of their shows, his feelings hidden from his face and voice; only the emotions flowing out of him reveal the pain he felt these past days. Although Jack's departure has tainted Sam's memories of him, there's a genuine hope, warmth, and awe that flows out of Sam as he speaks about him, and Castiel soaks in it, happy that Sam saw what he did. After all, it was Sam who taught him that good and evil was a choice, not a destiny. 

Sam talks about a house and ghosts and his breath catches in his throat. “And then Dean…” Grief flows out of Sam sharp and painful and Castiel lets it flow through him, losing himself in the bitter taste of it. The rage Sam keeps locked up and buried deep bubbles up and boils. It's the first time Castiel has ever felt Sam actually feeling his anger instead of burying deep, and it's so scorched and piercing it steals his breath away. He willingly burns himself on it. It's real and raw and he wants all of Sam, not just the parts Sam puts on display. 

Sam's angry at Dean, at the universe, maybe even at Castiel. For a moment Castiel awaits the rebuke he knows he deserves, but it never comes. Sam takes a deep breath and crams his anger back down into a tight little ball buried deep. “Dean died. He saw Billie - she's Death now.” 

A cold shiver threads its way through Castiel's remaining feathers, making them stand on nervous edge. He can only hope that his death was enough to satiate Billie’s thirst for vengeance; that he paid those cosmic consequences in full. 

“She said she has work for us.” Sam brushes imaginary dust off his thigh, his eyes on his hand. “You called after that. You know, Dean… Dean was certain you were gone forever,” Sam says, his eyes fixing on Castiel's, his pain subsiding and hope rising, a bright warmth that Castiel gladly absorbs. “But I always knew you'd come back to us.” 

Castiel yearns to be worthy of Sam's faith. “I'm sorry,” he says, wishing Sam could feel his honesty and regret, and understand how much he means it. “I shouldn't have knocked you unconscious or taken off with Kelly. I wanted to keep you safe from Lucifer, but I just put you in danger.” 

“You should know by now how stubborn we Winchesters are,” Sam teases with more warmth than Castiel deserves. If only the other angels could see what Castiel sees in Sam. To them, he's still an abomination, forever tainted by the demon blood forced upon him as a child. They don't see the incandescent blaze of his flayed soul and how it shines with such beauty despite the damage carved into it. They don't understand how powerful Sam’s forgiveness is or even what it means to really be forgiven. 

Sam stands and Castiel stands as well, ready to head out the door. 

Then Sam reaches down and yanks open the covers of his bed. “Wanna watch Netflix?” he asks without looking at Castiel. 

“Yes,” says Castiel as his fingers fly to his clothes. He's not sure how much Sam wants, so he keeps his shirt and boxers, but strips off everything else, dropping his clothes carelessly on the floor as he joins Sam in bed. It's a tight fit and they've got no choice but to press against each other; warm skin side by side, as Sam's emotions, even the ones he normally keeps buried deep, flow through Castiel. 

“Any new series since I've been gone?” Castiel can't bring himself to say ‘dead’ as the whole situation doesn't yet seem real. He breathes in the smell of Sam and the memories of the things they've done in this bed fill his cock and crowd his head, pushing out all rational thought. The humanity that remained with him after his grace was stolen is annoying at times like these, when his base, human desires make him dumb and unable to think rationally. He hates how much he helplessly wants this, _craves_ this. It's times like these that he wishes he were all angel again, so he wouldn't have to deal with these messy emotions that have stuck around even with the return of his grace. 

“I haven't watched any. Wanna finish the Life series?” Sam picks up the remote and clicks on the TV. 

“Sure.” 

The next episode is about insects. Sam flicks off the light in the room as soon as it starts. They lie in silence and watch the Darwin's beetle scuttle up the tree. 

Castiel tries to be content to just be there, lying by Sam, listening to Sam's breath and heartbeat. He feels Sam's pain and anger slowly recede. If only he could remove it all. He has the ability, but Sam would never allow it. Sam still hates the angel side of Castiel. Even a simple healing spell triggers the pain of what Lucifer and Gadreel did to him. What Castiel did to him. 

On the TV, butterflies tumble from their perches and land on the forest floor. They beat their wings furiously and the ones that can fly make it back to safety, while those without the strength to leave the ground freeze to death in the night, ice spreading out in a deadly lace on their beautiful, but fragile, wings. Castiel's own wings are broken - practically useless - but he would've never had this with Sam had he remained a perfect angel. Sometimes it almost seems an ideal trade - all that power and glory for Sam's forgiveness and affection - but often he feels as helpless as the fallen butterflies, desperate to find his way up and onto a new perch before the cold catches up to him while the light fades fast. 

It isn't long before Sam shifts down, dragging the covers with him as he moves to curl his fingers in the waistband of Castiel's boxers. They've done this often enough that they don't need to speak as they move into position. Castiel helps Sam strip him of his boxers before he moves to the head of the bed with his legs apart and his cock thick on his stomach. 

Sam settles between his legs, his warm mouth sucking Castiel in deep as he closes a hand around the base of Castiel's cock. It's exactly what Castiel had wanted but couldn't ask for, and he closes his eyes and sinks into the pleasure Sam gives so perfectly. Sam’s an expert at oral (Castiel doesn't think about why), and he knows just how to bob his head and work his throat, lips, and tongue until Castiel's arousal is flooding through him so thick and so hot, and his grace is alive, surging and pulsing and pure, and it's the closest he'll ever get to feeling whole again. 

Sam holds him there in bliss for what seems like forever, his mouth and hands keeping Castiel's pleasure at perfect pitch until his hips are desperately jerking, his cock hard and weeping, his balls tight and full, and his grace vibrates within and around him, bright and electric. His broken wings unfurl and flutter fruitlessly, each flap driving his pleasure higher and higher until he's almost soaring. 

He orgasms with a strangled cry, biting down on his lip and power to avoid blowing the bunker's fuses. His wings beat with each pulse of his cock as he pours himself down Sam's throat, careful to keep his energy flowing around Sam, not through him. 

For a moment, Castiel can't do anything but gasp for breath, his limbs turned to jello, and warm contentment flowing through him. 

Sam releases Castiel's softening cock with a satisfied smile on his lips. “I thought you were gonna blow the lights again.” 

“Almost did,” Castiel says breathlessly. 

Sam leaves the bed and eagerly strips off his shirt and pajama pants. His fat cock bobs between his legs as he steps over to the bedside table and rummages through the drawer. 

Castiel hurriedly unbuttons his shirt. Sam's desire is thick and heady and he wants, needs, to feel more of it. Unable to wait with Sam's arousal still so heavy, Castiel offers what he knows Sam needs. He gets into position on his hands and knees. “Go ahead. I'm ready.” 

“Are you sure?” asks Sam, hesitation and desire flairing. 

“I can heal myself,” Castiel reminds him. “Do it.” 

Sam must hear the want in his voice, and the hesitation vanishes as he hurriedly slicks up his cock and climbs onto the bed. He grabs Castiel's hip and presses the thick head of his huge cock inside, forcing him wide. Castiel heals himself until he feels nothing but pleasure as Sam pushes his chest flat against the bed and sets a punishing pace, bottoming out with each strong thrust. 

It's so fast and so hard and Sam's hitting him just right and his cock rises again, despite being so thoroughly satisfied just a moment before. He’d be permanently banned from heaven if the other angels saw the demon-tainted human using him like an animal and knew how much he enjoyed it. 

_“You have fallen in every way imaginable.”_

None of them have touched Sam's soul. None of them have been human enough to understand Sam’s guilt, his pain, his forgiveness. To them, Sam will always be the demon half-breed who was arrogant enough to think himself better than angels. But it wasn't arrogance or power that allowed Sam to wrestle an archangel and win. It was his ability to love, his _humanity_ that thwarted the apocalypse. 

Sam grabs Castiel's shoulders, pushing him hard against the bed as he drills into him. 

If Castiel were more human, he'd struggle to breathe, but he's angel enough to take it with ease, dizzy on the feel of Sam's pleasure coursing through him, a rich electrical current that fills him with heat and ecstasy, rippling his feathers and sending his grace pulsing again. 

Sam shifts slightly, setting one hand flat on the bed beside Castiel's shoulder as he grips the back of Castiel's neck and then- 

_A hand at his throat pins him on the hard floor and he can't breathe, his face wet with tears. It's freezing outside and in him as knees force his legs even more painfully wide, his hands free, but helpless to save himself from the ruthless invasion as each thrust pushes the cold deeper inside of him. Lucifer hisses in Enochian and Sam never understood those words, but Castiel knows all of them and he's frozen now, unable to breath or move or escape, and-_

“Him?” Sam asks. He's still and his hand is gone from Castiel's throat. 

“Yes,” says Castiel as he centers himself, focusing on every little detail around him, on the small light in the room and the way the shadows move, the feel of the white cotton sheets beneath his fingers, the smell of the old books and Sam's deodorant and sweat and shampoo. 

Sam pulls out carefully, his cock softening. “Just think about me,” says Sam, running a gentle hand down Castiel's back. “You're here, in the bunker, and Lucifer is locked far away in a completely different universe.” 

Castiel can't move; he’s exhausted and jagged and he doesn't know how Sam can stand to touch him, much less comfort him, after he released these memories in Sam - memories that should've stayed buried. He'd touched Sam's soul himself and he knew the risks, but he thought he could cure Sam, fix his head the way he fixed a broken leg or arm. But the small crack he'd put in the wall turned into a jagged fissure and the entire thing crumbled to dust; the memories too raw, too powerful to stay hidden. Once again, he's humbled, he's awed at Sam's strength, and he wishes he knew how to make Sam feel the way Sam makes him feel. 

“I don't deserve you,” he says. 

“Don't say that, man.” Sam says firmly, but patiently. “We've all fucked up.” 

Castiel pushes himself upright and turns to kiss Sam. He catches him off guard and, for a moment Sam just sits there in surprise, his eyes wide open, because he knows Castiel’s not interested in kissing. It's too human - too much like eating, with the taste of molecules - but Castiel wants it now because he knows Sam wants it. Or does he? Was this a mistake? For a moment, they just look at each other. Castiel expects Sam to once again say, “Dude, you're supposed to close your eyes when you kiss.” If not pull away completely. 

But then Sam closes his eyes and melts against Castiel, returning the kiss with a hungry tenderness, his strong arms wrapping around Castiel and pressing him tight. His tight brow loosens as contentment returns to his face. 

Sam breaks the kiss to say, “I missed you,” before he presses his mouth desperately against Castiel's again. Pain and grief rise in him and Castiel absorbs it as he cradles Sam in his arms. Sam's body is bigger than his own, and he's strong for a human, but he _is_ still human, and in these moments he's so small and vulnerable and _young_. Castiel just wants to wrap his wings around him, the way he sheltered Dean while he pulled him from hell. But he can't because Sam will remember Lucifer's wings. 

He knows now that's why Sam's soul stayed in the Cage. All other human souls long for the feel of angelic grace and naturally cling to it. Sam had mistaken him for Lucifer and pulled away. 

Sam's grief fades as his pleasure rises and Castiel feels the crescendo building again in both Sam's emotions and the hunger of his mouth. 

Sam abruptly pulls back to say, “For someone who hates kissing, you are damned good at it.” 

“I don't hate it,” Castiel says, “it just doesn't fill me with pleasure the way it does you.” 

“What does?” asks Sam, his voice low and his eyes heated. 

“Oral sex, anal sex, r-” 

Sam laughs and pulls away. He grabs the lube and tosses it to Castiel. “Wanna fuck me?” He lies back on the bed with his legs spread in open invitation. 

Castiel's soft cock springs to life at that thought. “Yes.” But this isn't about what he wants. “But I can't easily kiss you during it that way.” 

“You want to kiss me while having sex?” The swell of eagerness and desire in Sam is enough for Castiel to really mean it when he says, “Yes.” 

Sam hurriedly moves to sit in front of the baseboard. His cock is already hard again; kissing always turns him on. He watches with hungry eyes as Castiel drizzles lube all over Sam’s cock and mounts him, planting his feet firmly on either side of Sam's body. Castiel braces himself on the headboard, his fingers brushing against the pillows Sam's stuffed behind it to prevent it from banging against the wall. 

With his free hand, he guides Sam back inside him, feeling the stretch of his rim as he's opened up. Sam's cock is warm and thick, the same as his pleasure, and both fill Castiel up until he can't think of anything else but the feel of Sam moving in him and through him. He kisses Sam again, clumsy and breathless, his cock sliding against Sam's stomach with each thrust of his hips as he fucks himself slowly, savoring the moment. 

Sam's strong hands roam over Castiel's body as if he’s forgotten the touch of him in the time they were apart. He grabs his hair, his shoulders, his hips, his arms, everywhere as he kisses him with yearning and love, almost in prayer. 

Castiel doesn't understand how Sam can look at him and see something holy, something worthy of worship after all that he's done and how far he's fallen. Somehow Sam does, just as Sam had the faith to pray to him after he shattered Sam's wall. He's felt Sam's guilt often enough to know there's hope for personal redemption intertwined with his forgiveness and faith, but it's more than just that, it's Sam. It's why his soul burns so brightly even with its scars. 

Their arousal rises and rises until Castiel can no longer tell the difference between his and Sam's, they surge within him thick and exquisite. Losing himself in the deluge, Castiel closes his eyes and unfurls his wings, careful to keep them from touching Sam, as he spreads them wide, his grace pulsing through his quivering feathers. 

As if sensing what Castiel wants, Sam grabs Castiel's ass and holds him in place as he drills into him hard and deep, hitting him just right. Castiel no longer has to move or even think as his grace throbs, a torrent of pleasure that coalesces into an ever climbing peak. And he's in his human body and outside of it, physical and energy, wavelength and matter, his grace singing with the resonances of electromagnetic forces across the universe. 

And he's pulsing higher and higher, and it's almost like flying, almost like being in heaven, but different, and better. And then, he shatters. 

Swell after swell flows through him, down his spine, out through his wings, each feather trembling, his grace swirling and flowing in him and around him. Peace, contentment, warmth. He slowly comes back to rest fully in his vessel, his wings tucking in again. 

Castiel opens his eyes to pitch black except for the glow from Sam's alarm clock. 

“Fuck,” says Sam as he gasps for breath. 

“Sorry,” says Castiel as his limbs tremble and he carefully pulls himself off Sam's softening cock. He knows it's a pain to fix the fuses, and his grace flowed through Sam. 

Sam chuckles as warm amusement drifts out of him and into Castiel. “I did it on purpose.” He kisses Castiel lovingly and says, “I wanted to see you lose control. You wanna clean us up?” 

The request catches Castiel off guard, but he trusts Sam to know his limits. They've made a mess. Come drips out of his ass and covers Sam's chest. He presses his hand to Sam's abdomen and uses his grace to clean them both of sweat and come. 

There's only a small flair of panic this time. Castiel wouldn't have noticed had he not been searching for it. It's gone almost as soon as it appears, Sam's heartbeat soon returning to its steady pace. They dress in comfortable silence. Sam tosses Castiel the t-shirt he usually wears in this room and Castiel’s breath hitches at the sight of it - that Sam had it tucked in a drawer all this time with the expectation it would be worn again. 

“I still have the book you were reading last time,” Sam says, nodding to his desk, where Castiel's copy of _Do Androids Dream of Electronic Sheep_ is resting on top of a neat pile. 

“You want me to stay then?” Castiel asks, just to be sure. Sam is fairly logical and even keeled, but he’s still human, which means Castiel never quite knows what he wants. 

“If you want to,” Sam says as he tucks himself in bed, leaving enough room for Castiel to join him. 

“I would.” Castiel retrieves his book and settles in next to Sam. It's a small bed, but they make it work. 

**Author's Note:**

> I came up with this idea as basically a writing challenge because I struggle with Dean's voice and I wanted to try to write 3 distinct voices. This story was the hardest of the three to write (yet I finished first) because they kept dragging it off in different directions. It's made me really want to write a longer, proper Sastiel since PWPs are a pain because they enjoy talking to each other way too much. 
> 
> Your comments and kudos give me life. Please let me know what you think. Also please let me know if I actually pulled off my little experiment to write 3 distinct voices.


End file.
